The 25-year-old has been forced to play second fiddle to star striker Robert Lewandowski since joining die Schwarzgelben from Stuttgart for €5.5 million (£4.5m) in 2012 and has only been afforded six Bundesliga outings by coach Jurgen Klopp this season.

Poland international Lewandowski has already announced he will be leaving Dortmund for Bayern Munich at the end of the current campaign, but Schieber still suspects his prospects of first-team football would be better served by a move away from Signal Iduna Park this summer.

“I have to take a decision on my future," the former Germany Under-21 international told Goal. "I cannot lie to myself: I am thinking about leaving.

"You just have to take a look at my stats and be honest. Compared to my first year here, [the number of games I've played this season] is significantly less.

"There has been no progress and my aim was to make the next step."

Schieber insists, though, it would be difficult to part company with Dortmund, and he can fully understand why he has been restricted to the role of substitute, given Lewandowski's consistent brilliance.

“It is an exciting and beautiful time here but from a sporting perspective there have been disappointments,” he added.

“I want to play more often, obviously. When I decided to join BVB, I knew Robert was the number one striker. He plays fantastically week in, week out. That makes it difficult for me.

“Nonetheless, I have played only six times this year and, altogether, I have only been on the pitch for half an hour. This situation is unsatisfying and I am lacking self-confidence.”